Consumer appliances such as dishwashers of various types have been proposed wherein items are placed in a wash chamber which is filled and emptied according to desired wash sequences. Recently, dishwasher manufacturers have focused even more on efficiency in implementing new designs. Thus, an amount of electricity, an amount of detergent, and an amount of water used are all monitored in an attempt to provide efficient and environmentally sensitive machines.
One approach for improving efficiency has been using feedback as to measured qualities of the water being used in a given cycle. For example, turbidity of water being cycled through as dishwasher can be measured and used to optimize the cycle to only use as much water as is needed to clean a given load. The amount of water could vary, in some cases, depending on the type of items being washed, the amount of items being washed, and the cleanliness of the items being washed before the wash cycle starts. In some cases, for example, people will rinse off dishes in a sink before placing them in a dishwasher. Doing so can reduce the need for pre-washing to remove debris.
U.S. Pat. Nos. 5,555,583 and 5,560,060, owned by Applicants' Assignee, and incorporated by reference herein, both disclose use of such turbidity measurements to improve cycle efficiency. The methods disclosed in the patents also use water temperature information to help fine tune the measurements, since turbidity readings often vary with temperature. While the devices and methods disclosed therein work well for their intended applications, efficiency improvements are always welcome.
Accordingly, other designs for turbidity sensing devices and related consumer appliances and dishwashers including those addressing one or more drawbacks of conventional devices and dishwashers would be welcome.